Motor Swap SectionTech and Follow-My-Build Threads for members looking to put a different engine in their Mustang

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1996 Swap- 3.8 to 3.8

Firstly, let me thank everybody that contributes to the tech forums here. They have been a huge help over the past week!

I needed an engine swap into my 1996 Mustang with a 3.8l / automatic. The engine that went in is from a 1998 Mustang with a 3.8 / manual. I am just about done, and only ran into a few snags. I am not swapping the transmissions (yet, though I did buy everything to do that further down the road).

The new(to me) engine is in. It runs. It drives. There was 1 vacuum lead that was on the intake plenum that was not on my 1996, which I just plugged and it seems to be fine.

My problems-

1.) The "Overdrive Off" light is blinking. The car seems to be shifting fine. I left the transmission in the car during the swap, but I did drop the pan and change the filter and fluid (Mercon V). There is nothing observable aside from the light that indicates there is a problem with the tranny.

2.) The temperature gauge does not seem to be working. The engine gets warm, coolant circulates through the upper and lower hose, the heater blows warm, but the gauge does't move off of cold. This gauge worked before the swap, and I verified that new(to me) engine worked properly prior to buying (it was in a rear ended car that I started, revved, and allowed to warm up). The temperature gauge worked fine when the engine was in the donor car.

There is information available on both of these, and I used the search function to look for solutions. I will find a way to get the codes read tomorrow regarding the flashing OD light.

I don't know if there are specific "go-to's" I should check out that are more likely because these problems are the result of the engine swap?

Any suggestions?

Thanks!

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So the "Overdrive Off" light was simple enough to figure out. Reading the code pointed me to the OSS sensor, which is mostly on top of the transmission. It somehow became unplugged when I pulled the motor.

The temp gauge still does not work. I have found out that the new (1998) engine uses a different Temp Sending Unit then the 1996 engine.

Obviously the difference is the plug. They thread into the same spot near the thermostat, and I moved over the entire harness so the sensor is plugged in, but the gauge (which is the original 96 set up) seems to not work with the 98 sending unit/harness. How can I remedy this? I assume splicing may be involved...
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Also, the CEL is on and the code is p1443. This pointed to the Purge Control Valve. It is located near the passenger wheel well and the firewall.
It looks like this-http://578e7a9bafc08e847f59-b21544d4...4606a_7618.jpg

I only have on vacuum line running to this, and the other side isn't plugged into anything! Should there be two lines running two this? Where do they originate?

I needed an engine swap into my 1996 Mustang with a 3.8l / automatic. The engine that went in is from a 1998 Mustang with a 3.8 / manual. I am just about done, and only ran into a few snags. I am not swapping the transmissions (yet, though I did buy everything to do that further down the road).

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